The Lichenologist 47(1): 35–42 (2015) 6 British Lichen Society, 2015 doi:10.1017/S0024282914000553 The lichen genus Kroswia is a synonym of Fuscopannaria (Pannariaceae) Nicolas MAGAIN and Emmanue¨l SE´ RUSIAUX Abstract: Molecular inferences of three loci within a phylogenetic framework of a subset of the Pannariaceae confirm that the genus Kroswia is nested within the genus Fuscopannaria. The formal combination of the type species of Kroswia into Fuscopannaria is therefore made here, and Kroswia is reduced into synonymy with the latter genus. Key words: ascomycota, cyanolichens, morphology, Nostoc, Peltigerales, taxonomy Accepted for publication 6 October 2014 Introduction lichenized with cyanobacteria usually be- longing to the genus Nostoc. Such cephalodia A persistent question in the Pannariaceae,a may develop thalloid forms, sometimes pro- well-known and cosmopolitan lichen family, duce fragments that act as vegetative dia- lies with the assignment of taxa with collema- spores (Jørgensen & Wedin 1999), or may toid thalli, that swell considerably and form resemble autonomous entities recognized gelatinous masses when wet and quickly re- as a different genus, namely Santessoniella turn to a crispy and fragile form when dry, Henssen. unlike typical members of the family that de- A recent study conducted by the authors velop a ‘pannarioid’ thallus that does not (Magain & Se´rusiaux 2014) could provide swell when wet (Wedin et al. 2009; Ota´lora strong support for two interesting evolution- et al. 2010). Species in the genus Kroswia P. ary patterns within that family. Indeed, a M. Jørg. develop thalli of the former type, photobiont switch between two different typically homoiomerous with an indistinct strains of Nostoc is suspected to be the driver cortex, the photobiont forming chains of for the change in thallus type (pannarioid cells with much swelling sheaths and present thallus to collematoid type) within a strongly thoughout the thallus; species with a typical supported clade comprising the genera Fus- ‘pannarioid’ thallus such as in the genus Fus- copannaria, Kroswia, Leciophysma Th. Fr. copannaria P. M. Jørg. develop heteromerous and Protopannaria (Gyeln.) P. M. Jørg. & S. thalli with a distinct upper cortex and a very Ekman. Photobiont switches have been shown distinct photobiont layer with photobiont or are suspected to play a crucial role in spe- cells compacted and assembled in clusters. ciation processes of lichens (examples in Ba- A further interesting matter within the loch & Grube 2006; Nelsen & Gargas 2008; same family is the occurrence of tripartite Ferna´ndez-Mendoza et al. 2011; Printzen thalli, which are lichenized with green algae et al. 2013) and the molecular inferences in but produce well-differentiated structures, a phylogenetic context do support such a usually referred to as cephalodia, which are scenario for the genus Fuscopannaria. Furthermore, cephalodia emancipation from ancestral tripartite thalli followed by N. Magain and E. Se´rusiaux : Evolution and Conser- divergence is supported by the data and may vation Biology, University of Lie`ge, Sart Tilman B22, B-4000 Lie`ge, Belgium. represent an evolutionary pattern present Email : [email protected] throughout the family; it may explain the 36 THE LICHENOLOGIST Vol. 47 morphological resemblance between the thalli 25% of the trees sampled were discarded as burn-in, of several genera with cephalodia of others, as and a 50% consensus tree was produced using the remaining trees. Convergence of the analyses was well as the complex phylogenetic relationships assessed using Tracer (Rambaut & Drummond 2007) between species with tripartite thalli and and AWTY (Nylander et al. 2008) as implemented on others with collematoid or pannarioid thalli. the website http://king2.scs.fsu.edu/CEBProjects/awty. A convincing example of this evolution pat- tern is provided by the free-living Santesso- niella polychidioides (Zahlbr.) Henssen, liche- Results nized with Nostoc, which is nested with strong support within the tripartite genus Psoroma The phylogenetic tree (Fig. 1) presented here Ach. ex Michx. (Ekman et al. 2014) and can is the Bayesian 50% consensus tree with eval- be interpreted as the emancipated cephalo- uation of branch support from the Maximum dia of its tripartite ancestor which eventually Likelihood results and the posterior probabil- diverged. ities of the Bayesian search; 2666 characters This study aims to confirm the finding by from four loci (5.8 S, mtSSU, nuLSU and Magain & Se´rusiaux (2014) that the collema- RPB1) are included for 42 accessions repre- toid genus Kroswia is nested in Fuscopannaria senting 38 taxa. and to resolve their relationships by produc- As in earlier studies (Ekman et al. 2014; ing a phylogenetic tree including all data Magain & Se´rusiaux 2014), the genus Fusco- available in Fuscopannaria. As three acces- pannaria is retrieved as a monophyletic group, sions of its type species (K. crystallifera P. M. divided into two strongly supported clades, Jørg.) are found nested within Fuscopannaria accepting that F. sampaiana (Tav.) P. M. with strong support, the taxonomic and Jørg. is assigned to a different genus (Nevesia: nomenclatural conclusions are drawn in this Ekman et al. 2014) and with the exception paper. of F. laceratula (Hue) P. M. Jørg. which is resolved within a strongly supported and related lineage comprising Protopannaria Material and Methods pezizoides P. M. Jørg. & S. Ekman. The first clade within Fuscopannaria includes, among All sequences used in the phylogenetic analyses were downloaded from GenBank (Table 1). Those produced others, the type species [F. leucosticta by Ekman et al. (2014) in a revised classification of Pan- (Tuck.) P. M. Jørg.] and the three accessions nariaceae and Magain & Se´rusiaux (2014) for the taxa of Kroswia crystallifera, whilst the second one dealt with in this paper are thus included. We assembled includes, among others, the monotypic genus a concatenated matrix of three loci: mtSSU, nuLSU and Moelleropsis nebulosa (Hoffm.) Gyeln. RPB1 using MacClade v. 4.08 (Maddison & Maddison 2005). Ambiguously aligned positions were delimited by eye and excluded from the phylogenetic analyses. The alignment was divided into six subsets: mtSSU, nuLSU, RPB1 1st, 2nd and 3rd codon positions, and the intron Synonymy of Kroswia and new in RPB1. The best partition for the dataset was esti- combination in the genus Fuscopannaria mated using PartitionFinder (Lanfear et al. 2012) using AICc as a criterion and testing all models available with The phylogenetic relationship of Kroswia the greedy algorithm. The partition selected consisted of crystallifera, the type species of Kroswia, is 5 subsets: LSU and the 1st codon of RPB1 together, and similar to Moelleropsis nebulosa: although the every other subset by itself. overall morphology strongly deviates from We produced a best ML tree using RaxML-HPC2 v. 8.0.24 (Stamatakis 2006; Stamatakis et al. 2008) as im- the typical pannarioid thallus type of all spe- plemented on the CIPRES portal (Miller et al. 2010), cies assigned to that genus, the molecular using the GTRGAMMA model and 1000 bootstrap iter- data leave no doubt that both species must ations. A Bayesian analysis was performed using MrBayes be subsumed into Fuscopannaria (Ekman v. 3.2.2 (Huelsenbeck & Ronquist 2001) as implemented on the CIPRES portal, running for 20 million generations et al. 2014; Magain & Se´rusiaux 2014). with two runs of three cold chains and one heated chain Data on apothecial characters provided by each, and sampling every 1000th generation. The first Jørgensen (2007a) on another species [K. 2015 Kroswia is a synonym of Fuscopannaria—Magain & Se´rusiaux 37 Table 1. Table of the voucher specimens used in this study, with the species names and references to original publications; GenBank accessions of the sequences. GenBank Accession Number Taxon Country Publication mtSSU LSU RPB1 Fuscoderma applanatum New Zealand Wedin et al.2009 GQ259024 GQ258994 GQ259053 Fuscopannaria ahlneri South Korea Wedin et al.2009 GQ259025 GQ258995 GQ259054 F. cheiroloba Ekman et al.2014 — — KC608113 F. confusa Norway Carlsen et al.2012 GU570043 — — F. ignobilis Mia˛dlikowska et al.2006 DQ917416 DQ917417 DQ986839 F. lacerulata Ekman et al. 2014 KC608070 — KC608115 F. leucosticta 1 Reunion Island Magain & Se´rusiaux 2014 JX494238 JX494264 JX494284 F. leucosticta 2USAWedinet al.2009 DQ900630 DQ900640 GQ259055 F. leucostictoides Ekman et al.2014 KC608071 — KC608116 F. maritima Ekman et al.2014 KC608072 — KC608117 F. mediterranea Mia˛dlikowska et al.2006 DQ917418 DQ917419 — F. olivacea Ekman et al.2014 KC608073 — — F. pacifica Ekman et al. 2014 KC608074 — KC608118 F. praetermissa 1 Reunion Island Magain & Se´rusiaux2014 JX494239 — JX494285 F. praetermissa 2 Sweden Wedin et al. 2009 GQ259026 GQ258996 GQ259056 F. protensa Ekman et al.2014 — — KC608119 F. sorediata Ekman et al.2014 KC608067 — — Kroswia crystallifera 1 Madagascar Magain & Se´rusiaux 2014 JX494235 JX494261 JX494281 K. crystallifera 2 Reunion Island Magain & Se´rusiaux 2014 JX494236 JX494262 JX494282 K. crystallifera 3 Reunion Island Magain & Se´rusiaux 2014 JX494237 JX494263 JX494283 Leciophysma furfurascens Sweden Wedin et al. 2009 GQ259028 GQ258998 GQ259058 Moelleropsis nebulosa Ekman et al. 2014 KC608079 — KC608122 Nevesia sampaiana Norway Carlsen et al.2012/ GU570030 — KC608120 Ekman et al.2014 Pannaria calophylla Argentina Passo et al.2008 EU885318 — — P. implexa Argentina Passo et al.2008 EU885333 — — P. lurida Reunion Island